摘要
为解决航空发动机不同结构弯管振动带来的运行异常问题,以弯角和弯头长度为参数构建弯管分析模型,采用振动模态方法计算不同弯角和弯头长度下的弯管振动特性,同时对不同弯管模型进行振动模态试验,并将试验结果与数值仿真结果对比。结果表明:随着弯角变化,弯管模型1~4阶固有频率主要呈现减小趋势,但减小程度存在差异,结构主振型为弯曲与扭转不断叠加且振型幅度逐步增大;随着弯头长度变化,弯管模型5~9阶固有频率变化复杂,结构主振型为弯曲与扭转叠加,且位于管路中心的弯管两端振型较大。相对于直管,弯管模型振动特性变化复杂,从多角度研究其振动特征,可避开与发动机振动耦合的区间,提升弯管设计与使用的可靠性。
In order to tackle the abnormal operation problems caused by the vibration of the bending pipes of aero-engine system with different structural characteristics, the paper constructs the performance analysis models of the bending pipe with the different bending angles and the different pipe head lengths as the parameters. Then numerical simulation calculation is done to get the bending pipe vibration characteristics of the different bending angles and the pipe head lengths with the vibration modal analysis method. The results are analyzed and compared with the ones obtained by the vibration modal test of the bending pipes with different angles. The results show that the natural frequency of the same order of the models(1-4) mainly display the decreasing trend with small discrepancy along with the increase of bending angles, and the main deformation of the structure with bending superimpose torsion constantly and the amplitude of deformation increases gradually. Then the natural frequency of the same order of the models(5-9) display complex change with the increase of the length of the pipe head, and the main deformation of the structure is the same as the models(1-4) basically, except that the bending pipe with curved section located at the middle of the pipe is more affected. It is concluded that the vibration characteristics of bending pipe are complex with respect to the straight pipe. And it is necessary to analyze comprehensively the bending pipe vibration from multiple angles to keep away the vibration range generated by the coupling with the aero-engine vibration and thus improving the reliability of the design and use of the bending pipe in the aero-engine system.
作者
王志国
WANG Zhiguo(Engineering and Techniques Training Center,CAUC,Tiaryin 300300,China)
出处
《中国民航大学学报》
CAS
2022年第6期24-31,64,共9页
Journal of Civil Aviation University of China
基金
中央高校基本科研业务费专项(3122017108)。
关键词
航空发动机
弯管
弯角
弯头长度
振动特性
aero-engine
bending pipe
bending angle
pipe head length
vibration characteristics
